Jf. Power et Pt. Koerner, COVER CROP PRODUCTION FOR SEVERAL PLANTING AND HARVEST DATES IN EASTERN NEBRASKA, Agronomy journal, 86(6), 1994, pp. 1092-1097
Species used for cover crops vary greatly in their growth response to
water availability, soil temperature, length of growing period, day le
ngth, and related environmental factors. Few reports compare growth of
different species at different times during the growing season. This
4-yr field experiment at Lincoln, NE, compared growth of some 20 speci
es as affected by planting date and length of the growth period. All s
pecies were planted as early as possible each spring, with a second se
eding in early summer (25 June-17 July). Additional seedings were made
at other times in most years. All plots were periodically sampled for
dry matter production until maturity or frost. At most samplings, gro
wth of soybean [Glycine max L. (Merr.)] was equal to or greater than (
sometimes double) that of the next species. In most situations, hairy
vetch (Vicia villosa Roth) also performed well. Field pea (Pisum sativ
um L.) or Austrian winter pea [P. sativum L. subsp. sativum var. arven
se (L.) Poir.] and fava-bean (Vicia faba L.) grew very rapidly for the
first 60 to 90 d after planting. Lespedeza [Kummerowia stipulacea (Ma
xim.) Makino] grew relatively well when seeded in early summer, as did
tinga pea (Lathyrus tingitanus L.) and cowpea [Vigna unguiculata (L.)
Walp. subsp. unguiculata]. Rye (Secale cereale L.) was usually interm
ediate, and small-seeded legumes generally exhibited relatively slow g
rowth the first 60 d. Results suggest that certain large-seeded, cool-
season legumes would produce best for early spring seeding before row
crops or summer fallow, whereas some warm-season species would be bett
er suited for summer seeding after small grain harvest. Soybean and ha
iry etch were well suited for almost all situations in this environmen
t.